单选题The elements other than hydrogen and helium exist in such small quantities that it is accurate to say that the universe is somewhat more than 75 percent hydrogen. Astronomers have measured the abundance of helium throughout our galaxy and in other galaxies as well. Helium has been found in old stars, in relatively young ones, in interstellar gas, and in the distant objects known as quasars. Helium nuclei have also been found to be constituents of cosmic rays that fall on the earth (cosmic "rays" are not really a form of radiation; they consist of rapidly moving particles of numerous different kinds). It doesn"t seem to make very much difference where the helium is found. Its relative abundance never seems to vary much. In some places, there may be slightly more of it; in others, slightly less, but the ratio of helium to hydrogen nuclei always remains about the same. Helium is created in stars. In fact, nuclear reactions that convert hydrogen to helium are responsible for most of the energy that stars produce. However, the amount of helium that could have been produced in this manner can be calculated, and it turns out to be no more than a few percent. The universe has not existed long enough for this figure to be significantly greater. Consequently, if the universe is somewhat more than 25 percent helium now, then it must have been about 25 percent helium at a time near the beginning. However, when the universe was less than one minute old, no helium could have existed. Calculations indicate that before this time temperatures were too high and particles of matter were moving around much too rapidly. It was only after the one-minute point that helium could exist. By this time, the universe had cooled sufficiently that neutrons and protons could stick together. But the nuclear reactions that led to the formation of helium went on for only a relatively short time. By the time the universe was a few minutes old, helium production had effectively ceased.

单选题{{B}}Text 4{{/B}} The U. S. Bureau has estimated that the population of the United States could approach 300 million in 2000 and will be 400 million in 2020. And the U. S. Department of Commerce estimates that the average U.S. per capita income will increase from ＄3400 in 1969 to the equivalent of＄8300(assuming a 1967 price level) in the year 2000,2.5 times as much as that of 1969. According to government statistics, in the United States, there are over 110 million cars and "more people" means "more cars". By the end of twenties of next century, the population of the United States will have doubled that of today and the number of automobiles will be doubled as well. And in twenty-year's time the per capita income will also be 2.5 times higher than it is. If this increase income is spent on more and larger automobiles, larger houses, and increased consumption of other material goods, the results could cause catastrophic resource exhaustion, and pollution. Take the increase of the consumption of oil for instance. The consumption is so huge that the reserves might last only a decade or two if not supplemented by imports. Ten years ago it appeared that nuclear power would solve the anticipated energy crisis. Although supplies of uranium fuel were known to be limited and might become exhausted in half a century, the nuclear power plant has for a long time been a favorite project. But work on it has met with grave problems. The fear of possible atomic explosion and the problem of disposing of polluting by-product waste have slowed down the construction of further nuclear plants. Eventually atomic technology may be able to control these problems, but at present there seems to be little agreement among atomic scientists about when this can be achieved.

单选题When Dr. John W. Gofman, professor of medical physics at the University of California and a leading nuclear critic, speaks of "ecocide" in his adversary view of nuclear technology, he means the following. A large nuclear plant like that in Kalkar, the Netherlands, would produce about 200 pounds of plutonium each year. One pound, released into the atmosphere, could cause 9 billion cases of lung cancer. This waste product must be stored for 500,000 years before it is of no further danger to man. In the anticipated reactor economy, it is estimated that there will be 10,000 tons of this material in Western Europe, of which one table-spoonful of plutonium-239 represents the official maximum permissible body burden for 200,000 people. Rather than being biodegradable, plutonium destroys biological properties. In 1972 the .U.S. Occupational Safety and Health Administration ruled that the asbestos level in the work place should be lowered to 2 fibers per cubic centimeter of air, but the effective date of the ruling has been delayed until now. The International Federation of Chemical and General Workers' Unions report that the 2-fiber standard was based primarily on one study of 290 men at a British asbestos factory. But when the workers at the British factory had been reexamined by another physician, 40--70 percent had X-ray evidence of lung abnormalities. According to present medical information at the factory in question, out of a total of 29 deaths thus far, seven were caused by lung cancer. An average European or American worker comes into contact with six million fibers a day. "We are now, in fact, finding cancer deaths within the family of the asbestos worker," states Dr. Irving Selikoff, of the Mount Sinai Medical School in New York. It is now also clear that vinyl chloride, a gas from which the most widely used plastics are made, causes a fatal cancer of the blood-vessel cells of the liver. However, the history of the research on vinyl chloride is, in some ways, more disturbing than the "Watergate cover- up. " "There has been evidence of potentially serious disease among polyvinyl chloride workers for 25 years that has been incompletely appreciated and inadequately approached by medical scientists and by regulatory authorities," summed up Dr. Selikoff in the New Scientist. At least 17 workers have been killed by vinyl chloride because research over the past 25 years was not followed up. And for over 10 years, workers have been exposed to concentrations of vinyl chloride 10 times the "safe limit" imposed by Dow Chemical Company.

单选题Every year, thousands of college students apply for the CCTV Cup English Speech ______. A. Argument B. Quarrel C. Debate D. Contest

单选题According to the speaker, the basis of British habits of politeness is______.

单选题Sleep is a funny thing. We' re taught that we should get seven or eight hours a night, but a lot of us get by just fine on less, and some of us actually sleep too much. A study out of the University of Buffalo last month reported that people who routinely sleep more than eight hours a day and are still tired are nearly three times as likely to die of stroke--probably as a result of an underlying disorder that keeps them from snoozing soundly. Doctors have their own special sleep problems. Residents are famously sleep deprived. When I was training to become a doctor, it was not unusual to work 40 hours in a row without rest. Most of us took it in stride, confident we could still deliver the highest quality of medical care. Maybe we shouldn' t have been so sure of ourselves. An article in the Journal of the American Medical Association points out that in the morning after 24 hours of sleeplessness, a person' s motor performance is comparable to that of someone who is legally intoxicated. Curiously, surgeons who believe that operating under the influence is grounds for dismissal often don' t think twice about operating without enough sleep. "I could tell you horror stories," says Jaya Agrawal, president of the American Medical Student Association, which runs a website where residents can post anonymous anecdotes. Some are terrifying. "I was operating after being up for over 36 hours, "one writes. "I literally fell asleep standing up and nearly face planted into the wound. " "Practically every surgical resident I know has fallen asleep at the wheel driving home from work," writes another. "I know of three who have hit parked cars. Another hit a convenience store on the roadside, going [105kin/h]. " "Your own patients have become the enemy," writes a third," because they are the one thing that stands between you and a few hours of sleep. " Agrawal' s organization is supporting the Patient and Physician Safety and Protection Act of 2001, introduced last November by Representative John Conyers Jr. of Michigan. Its key provisions, modeled on New York State's regulations, include an 80-hour workweek and a 24-hour work-shift limit. Most doctors, however, resist such interference. Dr. Charles Binkley, a senior surgery resident at the University of Michigan, agrees that something needs to be done but believes "doctors should be bound by their conscience, not by the government. " The U. S. controls the hours of pilots and truck drivers. But until such a system is in place for doctors, patients are on their own. If you' re worried about the people treating you, you should feel free to ask how many hours of sleep they have had. Doctors, for their part, have to give up their pose of infallibility and get the rest they need.

单选题In education, changing patterns of school attendance required new ways of thinking. As late as 1870, 【C21】______families needed children at home to do farm work, Americans attended school for an average of only four years. By 1900, however, cities contained multitudes of children who had more time for school. Compulsory-attendance laws 【C22】______children to be in school to age fourteen, and swelling populations of immigrant and migrant children jammed schoolrooms. Before the Civil War, the curriculum had consisted chiefly of moral lessons. But in the late nineteenth century, the psychologist G. Stanley Hall and the philosopher John Dewey asserted that modern education ought to prepare children【C23】______. They insisted that personal development, not subject matter, should be the focus of the【C24】______. Education, argued Dewey, must relate directly to experience; children should be encouraged to discover knowledge for themselves. Learning 【C25】______to students' lives should replace rote memorization and outdated subjects. Progressive education, based on Dewey's books The School and Society(1899)and Democracy and Education(1916), was a uniquely American phenomenon. Dewey believed that learning should focus on real-life problems and that children should be taught to use their intelligence and ingenuity as 【C26】______for controlling their environments. From kindergarten through high school, Dewey asserted, children should learn 【C27】______direct experience. Dewey and his wife, Alice, put these ideas into【C28】______in their own Laboratory School, located at the University of Chicago. A more practical curriculum became the driving principle behind reform in higher education as well. Previously, the purpose of American colleges and universities had resembled that of European 【C29】______: to train a select few individuals for careers in law, medicine, teaching and religion. But in the late 1800s, institutions of higher learning multiplied. Curricula【C30】______as educators sought to make learning more appealing and to keep up with technological and social changes.

单选题The process of fermentation is ______ by adding sugar.

单选题Women are often said to be more ______ than men. A. emotions B. motions C. emotional D. emotive

单选题Not until the mid-12th century______as a nation with its own culture and language.

单选题{{B}}Passage Four{{/B}} What makes Reader's Digest the most successful magazine in publishing history? Beneath the fun and excitement that fill our pages, we are, above all else, a serious magazine. Our readers are serious people. The Digest never loses sight of the fact that each day all of us confront a tough, challenging world. To millions who know our record of viewing this world, we are not a luxury; we are a necessity. Basic to our magazine is a steady focus on the power of the individual. We show that man's greatest ideas and accomplishment, his often stunning (极好的) faith and courage and hope, can be seen in the conduct of ordinary men and women. We reflect the universal skepticism that government can solve our problems; we herald the unending promise of self-determination and individual enterprise. Readers depend upon us for truth and accuracy, logic and common sense. Our stories come from the grit of human experience—the tough, the tender, the funny. These Stories—always told in a powerful narrative style—spring from tore and caring, from a sense of right and wrong, from a dedication to the vitality (活力,生命力) of the human spirit. We are at the forefront of major issues of medicine, health, environment, human rights. We take readers behind the headlines to the cause and meaning of world events. We celebrate courage, champion adventure and always seek to expand the mind, and to enrich the spirit and the body. It is this clear voice—never preaching (说教), always showing—that has made readers set us apart from all other magazines. Deep within our widely varied package of humor, drama, and helpful information, there hums (哼唱) a subtle power that guides people in every aspect of their lives. They listen because what we put forth rings true. They are comfortable with our clear, concise words that inform them, entertain them, and remind them of those eternal values that fortify all decent people as they seek clarity and coherence in a confusing world. Our readers recognize that our compass is good for the long haul—that our principles are good for all seasons, good for all ages, good for all those who wish to play a role in making their world a better place. So long as we never lose sight of these powerful principles that are at the soul of our magazine—and so long as we remain at the cutting edge of life in our world—then we are prepared to lay claim to a future as brilliant and as exciting as our past.

单选题Education benefits a lot from multimedia because ______. A．all educational software employing multimedia is available in the libraries B．the material of education is dependent upon responses and requests of the students involved C．teachers can reduce their heavy work D．information can be controlled in the classroom

单选题Is ______ three hours ______ the boy ______ family is poor to come to school on foot? A) it; that; whose B) it; that it takes; whose C) it for; that it takes; whose D) it; when; that

单选题When a student, I was a member of the collegiate basketball team. It was mainly composed of bookish students. Only one could be counted as natural athlete, another half-qualified. That's why we were defeated nine out of ten games. Our spirits, however, had never dampened, for we were a cheerful team. None would strive to get into the spotlight when we were gaining the upper hand~ nor would we blame each other when we were losing. Thus a cordial relationship between members prevailed in our team. Most recommendable of all was our morale which never lowered. Our sportsmanship also remained good. We persisted in carrying on to the last when suffering great loss. We knew we had done our best, showing no regret at failure. To the rest of the students our team was a good one though it lost the game. They kept encouraging us and none of them was disappointed. Recently I have avoided watching games, not even at a TV live coverage, still less to the match in person. That's because I know I couldn't control myself. When watching a match, I'll inevitably take sides and be emotionally involved, strongly wishing for the triumph of the side over its opponent. As I often side with the "weaker " in a match, watching it will only spell worry and misery for me. Not long ago when I accompanied my wife to a super world tennis match my horizons broadened as regards sports competition. It seemed to me that wins and losses were relative and transient. What mattered was the ever-higher level achieved through contest. Victory was a result of all the efforts made by both sides. As one of the audience, I should applaud the energetic performance of both to the neglect of the result. Why should I regard the contest as a life-and-death struggle, the winner as survival and the loser as dead?

单选题The child was ______. he made up a wonderful story when he was given only the beginning of it. A) imaginative B) imagining C) imaginary D) imagery

单选题Sometimes, people (41) your life and you realize that they are there (42) some purpose, to (43) you a lesson, or to help you (44) who you are or who you want to become. You'd never know who these people (45) be, your friend, your classmate, your neighbor, your co-worker, your teacher, or (46) a stranger, but they will deeply (47) your life in some way. And sometimes things (48) to you that may seem (49) , painful and horrible at first, but (50) , you realize that without (51) those difficulties you would never know your strength, (52) or potential. Everything happens for a (53) . Nothing happens by (54) or by means of good luck. Illness, great achievement, love, injury and failure all come to (55) the limits of your soul. Without these tests, life would be like a straight and fiat road, but it goes (56) . It would be safe and comfortable, but dull and completely (57) . Those people who affect your life, and the failure and the success you experience can help you to create who you are and who you become. Even the bad experiences can (58) from. In fact, they are the most important ones. If someone breaks your heart, or hurts you, please (59) them, for they helped you to learn about the importance of being careful when you open your heart. If someone loves you, love them (60) , because they are teaching you to love and how to open your heart and eyes to things.